JPS6241124Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to an expansion tank that is installed in the water passages of instantaneous water heaters, etc., or the hot water circulation waterways of hot water heating equipment, and absorbs the expansion pressure of these waterways. To provide an expansion tank with a large expansion margin even under high pressure compared to other products.

As shown in Fig. 1, a conventional expansion tank houses elastic tubes 2 made of rubber, for example, which are spaced apart around the circumference and expand and displace in the outer circumferential direction due to pressure, in an outer cylinder 1, and the inside of the elastic tube 2 is connected to a waterway. They are communicated via a connecting pipe 3. In conventional examples with such a configuration, in order to secure the expansion capacity of the expansion chamber formed around the outer periphery of the elastic tube 2, the outer tube 1 has to be lengthened, or the diameter of the outer tube 1 has been increased. It is necessary to increase the volume of 1. However, in the latter case, there is a restriction due to the limit of elongation of the elastic tube 2, and therefore, in conventional products, the outer tube 1 is lengthened, and the length of the elastic tube 2 is also increased accordingly. However, in such conventional products, the distance between the fulcrums when the elastic tube 2 expands is long, and the expansion is large even at relatively low pressures, and when the pressure becomes high, the elastic tube 2 follows the inner wall of the outer tube 1, and under a constant high pressure, the elastic tube 2 almost never expands. There was no room for expansion.

The present invention solves the problems of the conventional products by increasing the withstand pressure against the elongation of the elastic tube, and will be specifically explained below based on an embodiment shown in the drawings.

Reference numeral 11 denotes an outer cylinder of the expansion tank, and the outer cylinder 11 has one end open, and a mounting flange 1 is attached around the opening 12.
3 is provided. Reference numeral 14 denotes an elastic tube made of rubber, for example, which is housed in the outer cylinder 1 at intervals around the periphery and has an expansion chamber 10 formed around its outer periphery. 16 are integrally formed. Reference numeral 17 denotes a lid to which a connecting pipe 18 is attached, one end of which communicates with a water passage of an instantaneous water heater, for example. The lid 17 is fixed to the mounting flange 13 of the outer cylinder 11 via the collar 16 of the elastic tube 14, and the outer Cylinder 11
The opening 12 of the elastic tube 14 and the opening 15 of the elastic tube 14 are kept watertight, and the elastic tube 14 is communicated with the water channel.
Further, an annular recess 19 is provided in the outer cylinder 11, and the recess 1
The tip of the elastic tube 9 is brought close to the elastic tube 14. In the other embodiment shown in FIG. 3, an annular projection 20 is integrally provided on the outer circumference of the elastic tube 14, and
A narrow portion 21 is provided in the expansion chamber 10 within the outer cylinder 11 so that the tip of the cylinder 0 is close to the outer cylinder 11.

The present invention has the above-described configuration, and when inflation pressure is applied to the elastic tube 14 through the connecting tube 18, the elastic tube 14
4 begins to expand in the outer circumferential direction, but the elastic tube 14 contacts the outer cylinder 11 at the narrow portion 21 at the initial stage of expansion, and as the pressure increases thereafter, the elastic tube 14 contacts the outer cylinder 11 as indicated by the broken line (Fig. 2,
As shown in FIG. 3), the narrow portion 21 serves as a fulcrum for the expansion of the elastic tube 14, and the elastic tube 14 is divided at this portion as a boundary.

Therefore, according to the present invention, when the elastic tube 14 expands, the distance between the fulcrums becomes shorter than that of the conventional product, and the pressure resistance against elongation becomes larger. It has an appropriate expansion margin even under high pressure.

In this way, the present invention has a significantly higher pressure resistance against elongation of the elastic tube than conventional products of the same volume, so it is possible to secure an appropriate expansion margin even under high pressure, and the product can be made smaller and less susceptible to pressure increases. Therefore, an extremely safe expansion tank can be provided.

In this embodiment, the narrow portion is provided at one location, but it may be provided at multiple locations, in which case the above effect will be even more remarkable.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a conventional example, FIG. 2 is a sectional view showing one embodiment of the present invention, and FIG. 3 is a sectional view showing another embodiment. 10... Expansion chamber, 11... Outer cylinder, 14... Elastic tube, 21... Narrow portion.

Claims (1)

[Scope of utility model registration request] An elastic tube that is spaced around the circumference and expands and displaces in the outer circumferential direction in an outer cylinder is housed, and an expansion chamber is formed on the outer periphery of the elastic tube, and a narrow part that the elastic tube abuts on the expansion chamber when expanded. An expansion tank characterized by being provided with.